This invention relates to electronic locksets and in particular to a control therefor which prevents the bolt of the lockset from being locked when the door is open.
Electronic locksets have gained increasingly widespread acceptance and use during the recent past. Such locksets are used in varied functions. For example, locksets are used in controlling egress and ingress through doors in hotels, office buildings, dormitories, classrooms, and the like. Although there are many similarities in the characteristics of the locksets used in the different functions, there are also significant differences.
For example, in a hotel function, it is desired for purposes of security that the outside hand operator remain in a locked or rigid state substantially at all times when the door is closed. The door may be opened from the outside solely by insertion into the lockset of a keycard (or the like) having a proper combination or code which actuates the locking mechanism of the lockset to permit the outside hand operator to be used for a rather limited time to retract the bolt.
The aforedescribed hotel lockset characteristic is not desirable for locksets providing a dormitory function. In the latter instance, the lockset should be capable of being placed in either an unlocked or locked state when the door is closed. In the unlocked state, the outside hand operator can be used to directly retract the bolt. The insertion of a properly coded keycard into the lockset to enable the door to be opened from the outside is not required when the lockset is in an unlocked state.
However, the dormitory function has its own rather unique requirement. To prevent the occupant of the room from being inadvertently or deliberately locked out, the bolt should be incapable of being electronically placed in a locked state when the door is open. Accordingly, it is an object of this invention to provide an electronic lock which can be utilized in applications requiring a dormitory function. It is a further object of the invention to unlock the bolt when the bolt has been retracted upon opening the door and to thereafter prevent the bolt from being locked while the bolt is in its retracted position.